The present invention relates generally to electric terminals and particularly to electric terminals for making an electrical connection to a threaded member.
A typical prior art approach to the problem of making an electrical connection to a threaded member is shown in FIG. 1 where stud type diode 40 and stud type diode 45 are to be mounted to bracket 42 through opening 44. When threaded portion 46 of diode 40 is electrically hot it must be insulated from bracket 42. Assembly parts for mounting diodes 40 and 45 may include insulating washer 48, insulating bushing 50, insulating washer 52, all of which may be made of mica or other suitable insulating material. Other assembly parts may include flat washer 54 and nut 56 which may be metallic. Lug terminal 60 includes mounting hole 59, conductor hole 61 and tab portion 63. Lug terminal 60 is intended to be secured to threaded portion 46 by nut 56. Assembled nut 56 forces surface 38 of diode 40 against surface 41 of bracket 42. Assembled nut 56 also insulating washer 48 and forces insulating washer 48 against forces insulating washer 52 against surface 43 of bracket 42 to secure diode 40 in place. Threaded portion 46 is engaged by the threads of nut 56 which makes electrical contact with threaded portion 46. Nut 56 also makes electrical contact with lug terminal 60 and secures lug terminal 60 between nut 56 and flat washer 54. After terminal lug 60 has been installed as described herein, tab portion 63 of lug terminal 60 is to be bent away from surface 43 of bracket 42 and a conductor is to be soldered to tab portion 63 at conductor hole 61. As illustrated in FIG. 1 a second stud type diode 45 is similarly mounted to bracket 42. Diode 45 is secured by nut 56' which also secures lug terminal 60,. Lug terminal 60' includes mounting hole 59', conductor hole 61, and tab 63'.
A problem with the prior art installation of FIG. 1 is that lug terminals 60 and 60' are in close proximity to surface 43 of grounded bracket 42 and therefore introduce the risk of lug terminal 60 or 60' coming in contact with surface 43 and producing a short. Typically the assembly instructions would direct the operator to bend tabs 63 and 63' of lug terminals 60 and 60' away from bracket 42 to eliminate the risk of shorting. How well the operator accomplishes these tasks determines whether a short will occur.
Bracket 42 is installed on chassis 64 as shown in FIG. 2. It is important to note that bracket 42 and chassis 64 are at ground potential while lug terminal 60 and 60' are electrically hot.
A second problem with the installation of FIG. 2 is the risk of tabs 63 and 63' being oriented so that one or the other of the tabs shorts against chassis 64. Again the assembly instructions would typically direct the operator to orient tabs 63 and 63' in a certain way. But again, how well the operator accomplishes these tasks will determine whether a short will occur.
In addition to the complications of properly bending and orienting tabs 63 and 63', the tabs increase the risk of catching items such as operator clothing, assembly tools, test tools, test leads or other items that will be near the lug terminals 60 and 60' during equipment assembly, testing or maintenance.